1. Field of the Invention
An apparatus consistent with the present invention relates to a disk drive and, more particularly, to a disk drive having an anti-shock structure for minimizing the collision between a head and a disk caused by an external impact.
2. Description of the Related Art
A hard disk drive is a data storage device used for reproducing/recording data from/on a rotating disk. A read/write head is mounted on an actuator and reproduces/records data on the rotating disk while being raised from a recording surface of the rotating disk by a predetermined height and moving to a predetermined location.
Recently, there has been an increasing demand for portable data storage devices. For a portable data storage device having a rotary actuator, it is desired to prevent the read/write head and a recording medium, such as, a disk, from colliding due to an external impact and thus damaging the head and the disk due to the collision.
FIG. 1 is a schematic perspective view of an example of a conventional disk drive; FIG. 2 is a plan view of a base member of the disk drive shown in FIG. 1; and FIG. 3 is a vertical sectional view of the disk drive shown in FIG. 1.
Referring to FIGS. 1, 2 and 3, the conventional hard disk drive includes a base member 10, a cover member 20, a spindle motor 40, and an actuator 50.
The spindle motor 40 for rotating the disk 30 is formed on the base member 10. To this end, a support 12 for the spindle motor 40 is mounted on the base member 10. The actuator 50 for moving a read/write head mounted on a slider 54 to a predetermined location on the disk 30 is rotatably installed on the base member 10. To this end, a pivot support 14 is formed on the base member 10, and an actuator pivot 51 is installed on the pivot support 14. An actuator arm 52 is coupled to the actuator pivot 51. A suspension 53 for elastically-biasing the slider 54 toward the surface of the disk 30 is installed at a front end of the actuator arm 52. The actuator 50 has a voice coil motor (VCM) 60 for rotating the actuator arm 52. The VCM 60 includes a VCM coil 61 coupled to a rear end of the actuator arm 52 and a magnet 62 facing to the VCM coil 61. The magnet 62 is usually attached to a yoke 63.
The VCM 60 rotates the actuator arm 52 in a direction conforming to Fleming's left hand rule by the interaction between a current flowing through the VCM coil 61 and a magnetic field formed by the magnet 62.
In particular, when the hard disk drive is turned on and thus the disk 30 rotates in the direction of an arrow D, the VCM 60 rotates the actuator arm 52 counterclockwise so that the slider 54 on which the head is mounted moves onto the recording surface of the disk 30. Meanwhile, when the hard disk drive is turned OFF and the disk 30 stops rotating, the VCM 60 rotates the actuator arm 52 clockwise so that the slider 54 deviates from the recording surface of the disk 30. After escaping from the recording surface of the disk 30, the head lands on a ramp 59 placed outside the disk 30.
In such a conventional hard disk drive, however, if an external impact is applied to the base member 10 in a direction approximately vertical with respect to the base member 10 with the slider 54 being located above the surface of the disk 30, the front end of the actuator 50 is bent down so that an intense rebounding force works between the slider 54 and the disk 30. For this reason, when the slider 50 moves down at a fast speed due to the resilience of the actuator arm 52 and the suspension 53 in the state where the head and the disk 30 are separated, the head collides with the surface of the disk 30. This is referred to as a “head slap”, which damages the head mounted on the slider 54 and the surface of the disk 30 and decreases the head's read/write performance.